Enhanced ∼2 μm emission in Tm3+ doped bismuth glasses by Ga2O3

The influence of B2O3 <-> Ga2O3 substitution on the - 2 mu m emission and gain properties of Tm3+-doped Bi2O3- B2O3 -BaF2 glasses was investigated by absorption, fluorescence, and Raman spectroscopy. It is shown that the thermal stability was enhanced as Ga2O3 replaces the B2O3 component gradually, while [GaO4] and [BO4] units enter the network. When the concentration of Ga2O3 reaches 8 mol% (BBG3 glass), the maximum gain coefficient at similar to 2 mu m reaches 10.89 cm(-1), which is larger than other glasses. Enhanced - 2 mu m emission and gain properties can be obtained by content Ga2O3 with the choice of 15 mol%. The W-ET of Tm3+ was calculated to reach 2051.7 x 10(-20) cm(3)/s, indicating that an effective cross-relaxation process can be obtained. The Tm3+ doped bismuth glasses show potential as similar to 2 mu m fiber amplifiers.